I doubt that a dealer is going to sit on a stockpile of things that he doesn't need anyway. Those chips would have been redeemed long ago.
On the same token, chips that are selling for let's say double face will in all probability not be redeemed.
The only collectors that have the potential for benefiting from this redemption are those that are in LV and at the casino when those chips are turned in.
I calculated that airfare from JFK N.Y. to LV is just slightly more expensive than paying a NIS a few bucks over face.
My time is also worth money . Even if I were in LV I wouldn't spend an hour or two of my time in line to save 3 Dollars.
Let the NIS guys make a living too. They certainly aren't getting rich doing it.